#pragma once

#include<iostream>
#include<sys/select.h>
#include<sys/time.h>
#include"Socket.hpp"

static const uint16_t defaultport = 8080;
static const int fd_num_max = (sizeof(fd_set) * 8);
int defaultfd = -1;

class SelectServer
{
private:
    Sock _listensock;
    uint16_t _port;
    int fd_array[fd_num_max]; // 辅助数组
public:
    SelectServer(uint16_t port = defaultport):_port(port)
    {
        for(int i = 0; i < fd_num_max; i++)
        {
            fd_array[i] = defaultfd;
        }
    }
    ~SelectServer()
    {
        _listensock.Close();
    }
    bool Init()
    {
        _listensock.Socket();
        _listensock.Bind(_port);
        _listensock.Listen();

        return true;
    }
    void PrintFd()
    {
        std::cout << "online fd list: ";
        for(int i = 0; i < fd_num_max; i++)
        {
            if(fd_array[i] == defaultfd)
                continue;
            else
                std::cout << fd_array[i] << " ";
        }
        std::cout << std::endl;
    }
    void Accepter()
    {
        std::string clientip;
        uint16_t clientport = 0;
        int sock = _listensock.Accept(&clientip, &clientport);
        if(sock < 0) return;
        lg(Info, "accept success, %s: %d, sock fd: %d", clientip.c_str(), clientport, sock);

        int pos = 1;
        for(; pos < fd_num_max; pos++)// second loop
        {
            if(fd_array[pos] != defaultfd)
                continue;
            else 
                break;
        }
        if(pos == fd_num_max)
        {
            lg(Warning, "server is full, close_fd is: %d", sock);
            close(sock);
        }
        else
        {
            fd_array[pos] = sock;
            PrintFd();
            //TODO
        }
    }
    void Recver(int fd, int pos)
    {
        char buffer[1024];
        ssize_t n = read(fd, buffer, sizeof(buffer)-1);
        if(n > 0)
        {
            buffer[n] = 0;
            std::cout << "get a message: " << buffer << std::endl;
        }
        else if(n == 0)
        {
            lg(Info, "client quit, me too! close_fd is: %d", fd);
            close(fd);
            fd_array[pos] = defaultfd;
        }
        else
        {
            lg(Warning, "recv error: fd is: %d", fd);
            close(fd);
            fd_array[pos] = defaultfd;
        }
    }

    void Dispatcher(fd_set &rfds)
    {
        for(int i = 0; i < fd_num_max; i++)// third loop
        {
            int fd = fd_array[i];
            if(fd == defaultfd)
                continue;

            if(FD_ISSET(fd, &rfds))
            {
                if(fd == _listensock.Fd())
                {
                    Accepter();//连接管理器
                }
                else // non listenfd
                {
                    Recver(fd, i);
                }
            }
        }
    }

    void Start()
    {
        int listensock = _listensock.Fd();
        fd_array[0] = listensock;
        for(;;)
        {
            //每次循环开始都要依据辅助数组重新设置fd_set
            fd_set rfds;
            FD_ZERO(&rfds);

            int maxfd = fd_array[0];
            for(int i = 0; i < fd_num_max; i++)// first loop
            {
                if(fd_array[i] == defaultfd)
                    continue;
                
                FD_SET(fd_array[i], &rfds);
                if(maxfd < fd_array[i])
                {
                    maxfd = fd_array[i];
                    lg(Info, "max fd update, max fd is: %d", maxfd);
                }
            }
            //不能直接accept，应该检验并获取listensock上的事件，新连接到来等于读事件就绪

            // struct timeval timeout = {1, 0}; // 输入输出，可能要进行周期的重复设置
            struct timeval timeout = {0, 0}; // 输入输出，可能要进行周期的重复设置
            // 如果事件就绪，上层不处理，select会一直通知你！
            // select告诉你就绪了，接下来的一次读取，我们读取fd的时候，不会被阻塞
            // rfds: 输入输出型参数。 1111 1111 -> 0000 0000

            struct timeval timeout2 = {2, 0};
            int n = select(maxfd + 1, &rfds, nullptr, nullptr, /*&timeout*/nullptr);//阻塞
            //int n = select(maxfd + 1, &rfds, nullptr, nullptr, &timeout2);// 2s
            switch(n)
            {
            case 0:
                std::cout << "timeout, timeout.tv_sec = " << timeout.tv_sec 
                    << ", timeout.tv_usec = " << timeout.tv_usec << std::endl;
                    sleep(1);
                break;
            case -1:
                std::cerr << "select error" << std::endl;
                break;
            default:
                //有事件就绪了
                std::cout << "get a new link!!!" << std::endl;
                Dispatcher(rfds);
                break;
            }
        }
    }
};